1 | // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause |
2 | /* |
3 | * Copyright(c) 2016 - 2018 Intel Corporation. |
4 | */ |
5 | |
6 | #include <linux/slab.h> |
7 | #include <linux/vmalloc.h> |
8 | #include "cq.h" |
9 | #include "vt.h" |
10 | #include "trace.h" |
11 | |
12 | static struct workqueue_struct *comp_vector_wq; |
13 | |
14 | /** |
15 | * rvt_cq_enter - add a new entry to the completion queue |
16 | * @cq: completion queue |
17 | * @entry: work completion entry to add |
18 | * @solicited: true if @entry is solicited |
19 | * |
20 | * This may be called with qp->s_lock held. |
21 | * |
22 | * Return: return true on success, else return |
23 | * false if cq is full. |
24 | */ |
25 | bool rvt_cq_enter(struct rvt_cq *cq, struct ib_wc *entry, bool solicited) |
26 | { |
27 | struct ib_uverbs_wc *uqueue = NULL; |
28 | struct ib_wc *kqueue = NULL; |
29 | struct rvt_cq_wc *u_wc = NULL; |
30 | struct rvt_k_cq_wc *k_wc = NULL; |
31 | unsigned long flags; |
32 | u32 head; |
33 | u32 next; |
34 | u32 tail; |
35 | |
36 | spin_lock_irqsave(&cq->lock, flags); |
37 | |
38 | if (cq->ip) { |
39 | u_wc = cq->queue; |
40 | uqueue = &u_wc->uqueue[0]; |
41 | head = RDMA_READ_UAPI_ATOMIC(u_wc->head); |
42 | tail = RDMA_READ_UAPI_ATOMIC(u_wc->tail); |
43 | } else { |
44 | k_wc = cq->kqueue; |
45 | kqueue = &k_wc->kqueue[0]; |
46 | head = k_wc->head; |
47 | tail = k_wc->tail; |
48 | } |
49 | |
50 | /* |
51 | * Note that the head pointer might be writable by |
52 | * user processes.Take care to verify it is a sane value. |
53 | */ |
54 | if (head >= (unsigned)cq->ibcq.cqe) { |
55 | head = cq->ibcq.cqe; |
56 | next = 0; |
57 | } else { |
58 | next = head + 1; |
59 | } |
60 | |
61 | if (unlikely(next == tail || cq->cq_full)) { |
62 | struct rvt_dev_info *rdi = cq->rdi; |
63 | |
64 | if (!cq->cq_full) |
65 | rvt_pr_err_ratelimited(rdi, "CQ is full!\n" ); |
66 | cq->cq_full = true; |
67 | spin_unlock_irqrestore(lock: &cq->lock, flags); |
68 | if (cq->ibcq.event_handler) { |
69 | struct ib_event ev; |
70 | |
71 | ev.device = cq->ibcq.device; |
72 | ev.element.cq = &cq->ibcq; |
73 | ev.event = IB_EVENT_CQ_ERR; |
74 | cq->ibcq.event_handler(&ev, cq->ibcq.cq_context); |
75 | } |
76 | return false; |
77 | } |
78 | trace_rvt_cq_enter(cq, wc: entry, idx: head); |
79 | if (uqueue) { |
80 | uqueue[head].wr_id = entry->wr_id; |
81 | uqueue[head].status = entry->status; |
82 | uqueue[head].opcode = entry->opcode; |
83 | uqueue[head].vendor_err = entry->vendor_err; |
84 | uqueue[head].byte_len = entry->byte_len; |
85 | uqueue[head].ex.imm_data = entry->ex.imm_data; |
86 | uqueue[head].qp_num = entry->qp->qp_num; |
87 | uqueue[head].src_qp = entry->src_qp; |
88 | uqueue[head].wc_flags = entry->wc_flags; |
89 | uqueue[head].pkey_index = entry->pkey_index; |
90 | uqueue[head].slid = ib_lid_cpu16(lid: entry->slid); |
91 | uqueue[head].sl = entry->sl; |
92 | uqueue[head].dlid_path_bits = entry->dlid_path_bits; |
93 | uqueue[head].port_num = entry->port_num; |
94 | /* Make sure entry is written before the head index. */ |
95 | RDMA_WRITE_UAPI_ATOMIC(u_wc->head, next); |
96 | } else { |
97 | kqueue[head] = *entry; |
98 | k_wc->head = next; |
99 | } |
100 | |
101 | if (cq->notify == IB_CQ_NEXT_COMP || |
102 | (cq->notify == IB_CQ_SOLICITED && |
103 | (solicited || entry->status != IB_WC_SUCCESS))) { |
104 | /* |
105 | * This will cause send_complete() to be called in |
106 | * another thread. |
107 | */ |
108 | cq->notify = RVT_CQ_NONE; |
109 | cq->triggered++; |
110 | queue_work_on(cpu: cq->comp_vector_cpu, wq: comp_vector_wq, |
111 | work: &cq->comptask); |
112 | } |
113 | |
114 | spin_unlock_irqrestore(lock: &cq->lock, flags); |
115 | return true; |
116 | } |
117 | EXPORT_SYMBOL(rvt_cq_enter); |
118 | |
119 | static void send_complete(struct work_struct *work) |
120 | { |
121 | struct rvt_cq *cq = container_of(work, struct rvt_cq, comptask); |
122 | |
123 | /* |
124 | * The completion handler will most likely rearm the notification |
125 | * and poll for all pending entries. If a new completion entry |
126 | * is added while we are in this routine, queue_work() |
127 | * won't call us again until we return so we check triggered to |
128 | * see if we need to call the handler again. |
129 | */ |
130 | for (;;) { |
131 | u8 triggered = cq->triggered; |
132 | |
133 | /* |
134 | * IPoIB connected mode assumes the callback is from a |
135 | * soft IRQ. We simulate this by blocking "bottom halves". |
136 | * See the implementation for ipoib_cm_handle_tx_wc(), |
137 | * netif_tx_lock_bh() and netif_tx_lock(). |
138 | */ |
139 | local_bh_disable(); |
140 | cq->ibcq.comp_handler(&cq->ibcq, cq->ibcq.cq_context); |
141 | local_bh_enable(); |
142 | |
143 | if (cq->triggered == triggered) |
144 | return; |
145 | } |
146 | } |
147 | |
148 | /** |
149 | * rvt_create_cq - create a completion queue |
150 | * @ibcq: Allocated CQ |
151 | * @attr: creation attributes |
152 | * @udata: user data for libibverbs.so |
153 | * |
154 | * Called by ib_create_cq() in the generic verbs code. |
155 | * |
156 | * Return: 0 on success |
157 | */ |
158 | int rvt_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr, |
159 | struct ib_udata *udata) |
160 | { |
161 | struct ib_device *ibdev = ibcq->device; |
162 | struct rvt_dev_info *rdi = ib_to_rvt(ibdev); |
163 | struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); |
164 | struct rvt_cq_wc *u_wc = NULL; |
165 | struct rvt_k_cq_wc *k_wc = NULL; |
166 | u32 sz; |
167 | unsigned int entries = attr->cqe; |
168 | int comp_vector = attr->comp_vector; |
169 | int err; |
170 | |
171 | if (attr->flags) |
172 | return -EOPNOTSUPP; |
173 | |
174 | if (entries < 1 || entries > rdi->dparms.props.max_cqe) |
175 | return -EINVAL; |
176 | |
177 | if (comp_vector < 0) |
178 | comp_vector = 0; |
179 | |
180 | comp_vector = comp_vector % rdi->ibdev.num_comp_vectors; |
181 | |
182 | /* |
183 | * Allocate the completion queue entries and head/tail pointers. |
184 | * This is allocated separately so that it can be resized and |
185 | * also mapped into user space. |
186 | * We need to use vmalloc() in order to support mmap and large |
187 | * numbers of entries. |
188 | */ |
189 | if (udata && udata->outlen >= sizeof(__u64)) { |
190 | sz = sizeof(struct ib_uverbs_wc) * (entries + 1); |
191 | sz += sizeof(*u_wc); |
192 | u_wc = vmalloc_user(size: sz); |
193 | if (!u_wc) |
194 | return -ENOMEM; |
195 | } else { |
196 | sz = sizeof(struct ib_wc) * (entries + 1); |
197 | sz += sizeof(*k_wc); |
198 | k_wc = vzalloc_node(size: sz, node: rdi->dparms.node); |
199 | if (!k_wc) |
200 | return -ENOMEM; |
201 | } |
202 | |
203 | /* |
204 | * Return the address of the WC as the offset to mmap. |
205 | * See rvt_mmap() for details. |
206 | */ |
207 | if (udata && udata->outlen >= sizeof(__u64)) { |
208 | cq->ip = rvt_create_mmap_info(rdi, size: sz, udata, obj: u_wc); |
209 | if (IS_ERR(ptr: cq->ip)) { |
210 | err = PTR_ERR(ptr: cq->ip); |
211 | goto bail_wc; |
212 | } |
213 | |
214 | err = ib_copy_to_udata(udata, src: &cq->ip->offset, |
215 | len: sizeof(cq->ip->offset)); |
216 | if (err) |
217 | goto bail_ip; |
218 | } |
219 | |
220 | spin_lock_irq(lock: &rdi->n_cqs_lock); |
221 | if (rdi->n_cqs_allocated == rdi->dparms.props.max_cq) { |
222 | spin_unlock_irq(lock: &rdi->n_cqs_lock); |
223 | err = -ENOMEM; |
224 | goto bail_ip; |
225 | } |
226 | |
227 | rdi->n_cqs_allocated++; |
228 | spin_unlock_irq(lock: &rdi->n_cqs_lock); |
229 | |
230 | if (cq->ip) { |
231 | spin_lock_irq(lock: &rdi->pending_lock); |
232 | list_add(new: &cq->ip->pending_mmaps, head: &rdi->pending_mmaps); |
233 | spin_unlock_irq(lock: &rdi->pending_lock); |
234 | } |
235 | |
236 | /* |
237 | * ib_create_cq() will initialize cq->ibcq except for cq->ibcq.cqe. |
238 | * The number of entries should be >= the number requested or return |
239 | * an error. |
240 | */ |
241 | cq->rdi = rdi; |
242 | if (rdi->driver_f.comp_vect_cpu_lookup) |
243 | cq->comp_vector_cpu = |
244 | rdi->driver_f.comp_vect_cpu_lookup(rdi, comp_vector); |
245 | else |
246 | cq->comp_vector_cpu = |
247 | cpumask_first(srcp: cpumask_of_node(node: rdi->dparms.node)); |
248 | |
249 | cq->ibcq.cqe = entries; |
250 | cq->notify = RVT_CQ_NONE; |
251 | spin_lock_init(&cq->lock); |
252 | INIT_WORK(&cq->comptask, send_complete); |
253 | if (u_wc) |
254 | cq->queue = u_wc; |
255 | else |
256 | cq->kqueue = k_wc; |
257 | |
258 | trace_rvt_create_cq(cq, attr); |
259 | return 0; |
260 | |
261 | bail_ip: |
262 | kfree(objp: cq->ip); |
263 | bail_wc: |
264 | vfree(addr: u_wc); |
265 | vfree(addr: k_wc); |
266 | return err; |
267 | } |
268 | |
269 | /** |
270 | * rvt_destroy_cq - destroy a completion queue |
271 | * @ibcq: the completion queue to destroy. |
272 | * @udata: user data or NULL for kernel object |
273 | * |
274 | * Called by ib_destroy_cq() in the generic verbs code. |
275 | */ |
276 | int rvt_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata) |
277 | { |
278 | struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); |
279 | struct rvt_dev_info *rdi = cq->rdi; |
280 | |
281 | flush_work(work: &cq->comptask); |
282 | spin_lock_irq(lock: &rdi->n_cqs_lock); |
283 | rdi->n_cqs_allocated--; |
284 | spin_unlock_irq(lock: &rdi->n_cqs_lock); |
285 | if (cq->ip) |
286 | kref_put(kref: &cq->ip->ref, release: rvt_release_mmap_info); |
287 | else |
288 | vfree(addr: cq->kqueue); |
289 | return 0; |
290 | } |
291 | |
292 | /** |
293 | * rvt_req_notify_cq - change the notification type for a completion queue |
294 | * @ibcq: the completion queue |
295 | * @notify_flags: the type of notification to request |
296 | * |
297 | * This may be called from interrupt context. Also called by |
298 | * ib_req_notify_cq() in the generic verbs code. |
299 | * |
300 | * Return: 0 for success. |
301 | */ |
302 | int rvt_req_notify_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags notify_flags) |
303 | { |
304 | struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); |
305 | unsigned long flags; |
306 | int ret = 0; |
307 | |
308 | spin_lock_irqsave(&cq->lock, flags); |
309 | /* |
310 | * Don't change IB_CQ_NEXT_COMP to IB_CQ_SOLICITED but allow |
311 | * any other transitions (see C11-31 and C11-32 in ch. 11.4.2.2). |
312 | */ |
313 | if (cq->notify != IB_CQ_NEXT_COMP) |
314 | cq->notify = notify_flags & IB_CQ_SOLICITED_MASK; |
315 | |
316 | if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) { |
317 | if (cq->queue) { |
318 | if (RDMA_READ_UAPI_ATOMIC(cq->queue->head) != |
319 | RDMA_READ_UAPI_ATOMIC(cq->queue->tail)) |
320 | ret = 1; |
321 | } else { |
322 | if (cq->kqueue->head != cq->kqueue->tail) |
323 | ret = 1; |
324 | } |
325 | } |
326 | |
327 | spin_unlock_irqrestore(lock: &cq->lock, flags); |
328 | |
329 | return ret; |
330 | } |
331 | |
332 | /* |
333 | * rvt_resize_cq - change the size of the CQ |
334 | * @ibcq: the completion queue |
335 | * |
336 | * Return: 0 for success. |
337 | */ |
338 | int rvt_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata) |
339 | { |
340 | struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); |
341 | u32 head, tail, n; |
342 | int ret; |
343 | u32 sz; |
344 | struct rvt_dev_info *rdi = cq->rdi; |
345 | struct rvt_cq_wc *u_wc = NULL; |
346 | struct rvt_cq_wc *old_u_wc = NULL; |
347 | struct rvt_k_cq_wc *k_wc = NULL; |
348 | struct rvt_k_cq_wc *old_k_wc = NULL; |
349 | |
350 | if (cqe < 1 || cqe > rdi->dparms.props.max_cqe) |
351 | return -EINVAL; |
352 | |
353 | /* |
354 | * Need to use vmalloc() if we want to support large #s of entries. |
355 | */ |
356 | if (udata && udata->outlen >= sizeof(__u64)) { |
357 | sz = sizeof(struct ib_uverbs_wc) * (cqe + 1); |
358 | sz += sizeof(*u_wc); |
359 | u_wc = vmalloc_user(size: sz); |
360 | if (!u_wc) |
361 | return -ENOMEM; |
362 | } else { |
363 | sz = sizeof(struct ib_wc) * (cqe + 1); |
364 | sz += sizeof(*k_wc); |
365 | k_wc = vzalloc_node(size: sz, node: rdi->dparms.node); |
366 | if (!k_wc) |
367 | return -ENOMEM; |
368 | } |
369 | /* Check that we can write the offset to mmap. */ |
370 | if (udata && udata->outlen >= sizeof(__u64)) { |
371 | __u64 offset = 0; |
372 | |
373 | ret = ib_copy_to_udata(udata, src: &offset, len: sizeof(offset)); |
374 | if (ret) |
375 | goto bail_free; |
376 | } |
377 | |
378 | spin_lock_irq(lock: &cq->lock); |
379 | /* |
380 | * Make sure head and tail are sane since they |
381 | * might be user writable. |
382 | */ |
383 | if (u_wc) { |
384 | old_u_wc = cq->queue; |
385 | head = RDMA_READ_UAPI_ATOMIC(old_u_wc->head); |
386 | tail = RDMA_READ_UAPI_ATOMIC(old_u_wc->tail); |
387 | } else { |
388 | old_k_wc = cq->kqueue; |
389 | head = old_k_wc->head; |
390 | tail = old_k_wc->tail; |
391 | } |
392 | |
393 | if (head > (u32)cq->ibcq.cqe) |
394 | head = (u32)cq->ibcq.cqe; |
395 | if (tail > (u32)cq->ibcq.cqe) |
396 | tail = (u32)cq->ibcq.cqe; |
397 | if (head < tail) |
398 | n = cq->ibcq.cqe + 1 + head - tail; |
399 | else |
400 | n = head - tail; |
401 | if (unlikely((u32)cqe < n)) { |
402 | ret = -EINVAL; |
403 | goto bail_unlock; |
404 | } |
405 | for (n = 0; tail != head; n++) { |
406 | if (u_wc) |
407 | u_wc->uqueue[n] = old_u_wc->uqueue[tail]; |
408 | else |
409 | k_wc->kqueue[n] = old_k_wc->kqueue[tail]; |
410 | if (tail == (u32)cq->ibcq.cqe) |
411 | tail = 0; |
412 | else |
413 | tail++; |
414 | } |
415 | cq->ibcq.cqe = cqe; |
416 | if (u_wc) { |
417 | RDMA_WRITE_UAPI_ATOMIC(u_wc->head, n); |
418 | RDMA_WRITE_UAPI_ATOMIC(u_wc->tail, 0); |
419 | cq->queue = u_wc; |
420 | } else { |
421 | k_wc->head = n; |
422 | k_wc->tail = 0; |
423 | cq->kqueue = k_wc; |
424 | } |
425 | spin_unlock_irq(lock: &cq->lock); |
426 | |
427 | if (u_wc) |
428 | vfree(addr: old_u_wc); |
429 | else |
430 | vfree(addr: old_k_wc); |
431 | |
432 | if (cq->ip) { |
433 | struct rvt_mmap_info *ip = cq->ip; |
434 | |
435 | rvt_update_mmap_info(rdi, ip, size: sz, obj: u_wc); |
436 | |
437 | /* |
438 | * Return the offset to mmap. |
439 | * See rvt_mmap() for details. |
440 | */ |
441 | if (udata && udata->outlen >= sizeof(__u64)) { |
442 | ret = ib_copy_to_udata(udata, src: &ip->offset, |
443 | len: sizeof(ip->offset)); |
444 | if (ret) |
445 | return ret; |
446 | } |
447 | |
448 | spin_lock_irq(lock: &rdi->pending_lock); |
449 | if (list_empty(head: &ip->pending_mmaps)) |
450 | list_add(new: &ip->pending_mmaps, head: &rdi->pending_mmaps); |
451 | spin_unlock_irq(lock: &rdi->pending_lock); |
452 | } |
453 | |
454 | return 0; |
455 | |
456 | bail_unlock: |
457 | spin_unlock_irq(lock: &cq->lock); |
458 | bail_free: |
459 | vfree(addr: u_wc); |
460 | vfree(addr: k_wc); |
461 | |
462 | return ret; |
463 | } |
464 | |
465 | /** |
466 | * rvt_poll_cq - poll for work completion entries |
467 | * @ibcq: the completion queue to poll |
468 | * @num_entries: the maximum number of entries to return |
469 | * @entry: pointer to array where work completions are placed |
470 | * |
471 | * This may be called from interrupt context. Also called by ib_poll_cq() |
472 | * in the generic verbs code. |
473 | * |
474 | * Return: the number of completion entries polled. |
475 | */ |
476 | int rvt_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry) |
477 | { |
478 | struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); |
479 | struct rvt_k_cq_wc *wc; |
480 | unsigned long flags; |
481 | int npolled; |
482 | u32 tail; |
483 | |
484 | /* The kernel can only poll a kernel completion queue */ |
485 | if (cq->ip) |
486 | return -EINVAL; |
487 | |
488 | spin_lock_irqsave(&cq->lock, flags); |
489 | |
490 | wc = cq->kqueue; |
491 | tail = wc->tail; |
492 | if (tail > (u32)cq->ibcq.cqe) |
493 | tail = (u32)cq->ibcq.cqe; |
494 | for (npolled = 0; npolled < num_entries; ++npolled, ++entry) { |
495 | if (tail == wc->head) |
496 | break; |
497 | /* The kernel doesn't need a RMB since it has the lock. */ |
498 | trace_rvt_cq_poll(cq, wc: &wc->kqueue[tail], idx: npolled); |
499 | *entry = wc->kqueue[tail]; |
500 | if (tail >= cq->ibcq.cqe) |
501 | tail = 0; |
502 | else |
503 | tail++; |
504 | } |
505 | wc->tail = tail; |
506 | |
507 | spin_unlock_irqrestore(lock: &cq->lock, flags); |
508 | |
509 | return npolled; |
510 | } |
511 | |
512 | /** |
513 | * rvt_driver_cq_init - Init cq resources on behalf of driver |
514 | * |
515 | * Return: 0 on success |
516 | */ |
517 | int rvt_driver_cq_init(void) |
518 | { |
519 | comp_vector_wq = alloc_workqueue(fmt: "%s" , flags: WQ_HIGHPRI | WQ_CPU_INTENSIVE, |
520 | max_active: 0, "rdmavt_cq" ); |
521 | if (!comp_vector_wq) |
522 | return -ENOMEM; |
523 | |
524 | return 0; |
525 | } |
526 | |
527 | /** |
528 | * rvt_cq_exit - tear down cq reources |
529 | */ |
530 | void rvt_cq_exit(void) |
531 | { |
532 | destroy_workqueue(wq: comp_vector_wq); |
533 | comp_vector_wq = NULL; |
534 | } |
535 | |